The present invention relates to a method of automatically initializing a mobile station during a test between the mobile station and the test equipment emulating a single cell of a cellular mobile communication system and a method of automatically performing a sequence of tests.
Mobile stations for cellular mobile communication systems have to pass a wide range of tests before making the mobile station available to the consumer market. Those tests verify e.g. the conformance to specified frequency ranges or the conformance to specified protocols for the mobile communication system as well as tests to evaluate the acceptance of the mobile station by the end user.
Preferably, all these tests shall be conducted automated and under pre-defined dedicated initial conditions to achieve deterministic results. It is of high importance that each test is independent and not influenced by the previous test of the mobile station. To achieve this, not only the cell emulated by a test equipment has to be re-initialized before each test, but also the mobile station. Initializing or re-initializing the mobile station means that the internal memory of the mobile station storing information about the previous radio link and mobile management parameters are deleted and/or set to a dedicated, pre-determined initial value.
Especially in test series with a large number of subsequently performed tests, a radio cell is established with each new test and the mobile station registers to this cell. The mobile station stores internally information of the cell it was previously registered to enabling a fast contact to the cell after a loss of the radio link.
In a test environment for performing a series of tests the emulated cell is always the same in terms of frequency, modulation and e.g. also in terms of broadcasted network identification. In this case, the mobile station assumes that this is always the same cell. In consequence the results of a test case may depend on the test results of the previously performed tests. This problem is only solved by a re-initialization of the mobile station before each test case.
Usually this re-initialization is achieved by a reboot of the mobile station. However, such a reboot is very time consuming, especially for sophisticated smart phones. An automatically processing of a reboot is elaborate and laborious. In some cases it is even required to apply special devices to perform this reboot or to perform tests manually.
In DE 103 34 127 A1 a remote controlled reboot function of a mobile station is described. The disclosed mobile station comprises a dedicated switch-on/off unit and a remote control unit. The remote control unit is connected to a command interface to receive remote control commands. A test equipment contains software to establish a connection independent of the radio interface of an emulated mobile communication system to communicate to the remote control unit of the mobile station. On receipt of a switch-off command a switched-on mobile station is switched-off by the switch-on/off unit of the mobile station invoking e.g. a standardized so called AT command. In the same way, a reboot of the mobile station can be initiated by sending a combined command to switch off and subsequently automatically switch on the mobile station.
This has the disadvantage that such a remote control unit has to be additionally implemented into each mobile station under test. Further on, some type of mobile stations do not support such a standardized set of commands to control a mobile station, e.g. to switch it off or to switch it on.
Therefore it is the object of the present invention to provide a method that resets the internal memory of a mobile station into a dedicated initial state, especially with regard to stored information about radio link functionalities exchanged in network protocols according the layer 1 to 3 of the OSI reference model of the emulated cellular mobile communication system.
A further object is to provide a method to automate the performance of a sequence of consecutive tests of a test series.